This is a comprehensive research proposal designed to improve the treatment of childhood cancer by conducting clinical investigations as a member of Childrens Cancer Study Group A (CCSGA) and by independently conducting other research which is directly related to the mission of CCSGA. This proposal is divided into six general categories: 1. Conducting Phase I, II and III clinical investigations as a member of CCSGA. 2. Exploring the therapeutic usefulness of new agents, new modalities, and new ways of using established agents both in group-wide studies and as an independent institution performing pilot studies for CCSGA. 3. Perform pharmacological and immunological studies to provide background information for CCSGA studies in progress and for future study development. 4. Study the natural history of selected childhood cancers to define the variables required for performance of statistically valid clinical investigations. 5. To provide appropriate medical and emotional supportive care to study patients to enhance the probability of success of the clinical investigations undertaken. 6. Develop chemotherapy program at the LA County-USC Pediatric Pavilion.